Azobenzene based inorganic salts for light modulated ionic conductivity in aqueous solution

Area of Science:

• Materials Science
• Photochemistry
• Electrochemistry

Background:

• Azobenzene derivatives are known for their photoresponsive properties.
• Ionic conductivity in solutions is crucial for electrochemical applications.
• Controlling conductivity with external stimuli like light is a key challenge.

Purpose of the Study:

• To synthesize azobenzene-based inorganic salts with alkali metal cations (Li+, Na+, K+).
• To investigate the photoisomerization-induced changes in ionic conductivity of these salts in aqueous solutions.
• To understand the relationship between molecular structure, aggregation, and light-modulated conductivity.

Main Methods:

• Synthesis of azobenzene-based inorganic salts.
• UV-Vis spectroscopy to monitor photoisomerization.
• Electrochemical measurements to quantify ionic conductivity.
• Microscopy to observe solution morphology.

Main Results:

• Successful preparation of lithium, sodium, and potassium azobenzene salts.
• Demonstrated reversible light-modulated ionic conductivity in aqueous solutions.
• Potassium azobenzene solution showed the highest ionic conductivity.
• Unique network-like aggregated morphology was observed in potassium azobenzene solutions, correlating with enhanced conductivity.

Conclusions:

• Azobenzene-based inorganic salts can exhibit light-controllable ionic conductivity.
• The cation choice significantly impacts conductivity, with potassium being optimal.
• Solution morphology, specifically network aggregation, plays a vital role in enhancing light-modulated ionic conductivity.